Due to a fix applied earlier today a bug was introduced that is causing bosses which have any ‘fixate’ abilities, meaning those that will fixate on and/or chase a certain player, to not function correctly. This is currently noticeable for most players on Atramedes in normal or heroic, and Ascendant Council and Sinestra on heroic, but affects a great number of other bosses throughout the game.

We have a fix currently in the testing stages but it will require realm restarts to apply. We’re currently anticipating rolling restarts to happen early tomorrow morning during off-peak hours. We apologize for any inconvenience for those attempting bosses tonight with these mechanics.

Guild Challenges Information
Zarhym wrote a couple of blue posts about Guild Challenges, it's not really a preview yet but at least we know where it's going now.

Originally Posted by Zarhym
(Blue Tracker)

We haven't shared much information about this feature because it's remained very much in development. That said, we're about ready to release Guild Challenges for testing on the PTR soon. We'll also be sharing more information on how Guild Challenges work in the near future.

[...] What about if Guild Challenges gave experience above the cap, functioning like rested experience and moving the cap further relative to the experience gained through completing said challenges?

Don't worry. I can read, I swear. I'm referring to experience and not rep.

Ok now you're just tormenting us Zar. How about a one-sentence teaser about what guild challenges actually are?
Built into the user interface, Guild Challenges will be separated into three categories: Guild Dungeon Run, Guild Raid, and Guild Rated Battleground. You just need to be in a guild group to complete each category a set number of times per week, earning your guild achievements, experience above the cap, and gold deposited into the Guild Vault (a lot more gold if the guild is level capped). We'll have more details for you probably by next week.

Are these challenges only going to be able to be completed at level 85? It would be nice to see some love for low-level members in the guilds!
As I understand it, you'll be eligible to contribute equally to things like the Guild Dungeon Run challenge, provided the dungeon you're running is level-appropriate for the guild group.

That's pretty disappointing. Isn't this what guilds are already doing anyway? I thought it would be more like guild quests that create a phased challenge somewhere in the world for your guild to complete. This just promotes even more LFG queueing while sitting in town. Some love for world zones in endgame please.
We're working on something sort of along these lines as a much more robust content feature for the future, but I can't put a date or patch number on that yet. It also won't necessarily be centered around guilds.

Was that ambiguous? I've never been ambiguous before, so I wouldn't know.

The Daily Blink - Mages Get A Slight Buff in 4.1
Another piece from The Daily Blink! Hopefully I made the warning big enough.

But, really, I don't think the warning is big enough. In a few hours all of us with a little common sense will have to get popcorn as we read through the new forum posts and comments freaking out about the patch notes.